1. Field of the Invention
This invention relates in general to a wireless device and method for placing emergency calls from such a wireless device, and more particularly to a wireless device provided with an emergency service call model that is uniform regardless of the particular modem utilized to place an emergency call in a multi-modal device.
2. Description of the Related Art
Wireless communication devices with interconnect signaling capability are required by the FCC to provide emergency interconnect services, i.e., 911 calls. e911 is short for Enhanced 911, a location determining technology advanced by the FCC that enables mobile, or cellular, phones to place 911 emergency calls and enables emergency services to determine the geographic position of the calling device. When a person places a 911 call using a traditional phone with landlines, the call is routed to the nearest public safety answering point (PSAP) that then distributes the emergency call to the proper services. The PSAP receives the caller's phone number and the exact location of the phone from which the call was made.
Prior to 1996, in the United States, 911 callers using a mobile phone would have to access their own service providers and get verification of subscription service before the call was routed to a PSAP. In 1996 the FCC ruled that service providers must allow a 911 to go directly to the PSAP without regard to verification of service. Under this ruling, a 911 call must be handled by any available service carrier even if the caller is not a paying subscriber of that particular service carrier.
A host of service providers are available today, many with their own unique frequency range and communication protocols. Compatible hardware and/or software is needed to communicate with each provider. Direct broadcast satellite, GPS, WiFi, and mobile phones all use wireless modems to communicate, as do most other wireless services today. Wireless modems come in a variety of types, bandwidths, and speeds. Frequently, the modems used to allow these devices to communicate are standard devices over which the portable device developer has limited or no access to evoke changes.
To allow a single device the flexibility to communicate on a variety of networks, many devices are now provided with multiple modems. However, portable devices with multiple modems encounter significant e911 capability differences depending on the particular modems and protocols used. For instance, an iDEN modem is configured to automatically redial an emergency call number if the initial dial attempt fails. In contrast, a GSM modem does not have this feature and requires input from the user before it will retry the call. A caller that is used to an automatically redialing iDEN modem that is in an area where their e911 call is processed through a GSM network would not expect that they need to manually retry the call in the event the initial attempt fails. Other such differences between the modems in a multi-modal device confuse or annoy the user at a time when they can least afford it—at the time of an emergency.
Therefore a need exists to overcome the problems with the prior art as discussed above.